Guys, I left HER why the FUCK do I care?

There was this girl I was dating on and off, we both are in grad school. I just got out of a serious relationship that was toxic to the core and she just sorta came along. We laughed, talked, and before you know it... we were romantically involved. She was great don't get me wrong... sex was fucking amazing... man I wish I could fuck her right now. Women no offense but we care how you are in bed, no one wants a dead fish. Men who say otherwise are full of themselves or confused on life. There are so many beautiful women in this world and after a while I got bored. Then the initial novelty faded and the fighting set in. The fucking fighting. I just want to drink a beer sometimes and watch tosh. Why do you women want to use that time to talk about "us." Go do a puzzle or something. My five year old nephew can keep himself better entertained. Moving on. I left her and of course she cried, they all do. First few weeks were fine for me but I'm guessing harder for her. She missed me I could see it in her eyes, we share mutual friends and I've bumped into her occasionally. Then out of the blue, come week 6 maybe, I missed her. I think I saw her start to move on and become more independent and that made me want her more. She changed her look up a little and the last time I saw her, she just looked sexy af. I miss other stuff about her too. It was easy with her. We could just talk and she'd always listen and provide good advice, nothing like my psycho pathological previous ex. I think unknowingly I closed all the doors,.. she won't even look at me. What do I do?